I'm 61yrs old. Three summers ago I weighed 285lb at 6' and could hardly walk 100 yards. I got back on my bike (with wife) and began to ride again. 30yrs ago we both road a lot. Not competitvely, but we did long distance touring and road daily. A few weeks ago I was diagnosed with 80% blockage in two heart arteries and 50% in a third. No stents were put in. I returned to riding with the admonishment I should pay attention to any heart pain and back off. We've been on spinning bikes in a group throughout the winter. I've dropped down to 225lb. Still overweight but last summer I did a 130mi solo with some serious hills. I ride with a HR monitor and push myself about as hard as I can. Then last week I took a spill and shattered my clavicle and broke three ribs. Doc says 2months of doing nothing with my left arm. I'm going to setup a mtn bike on a trainer outside using a time trial bar pointed vertically so I can hold it a bit with my right arm for balance. Maybe I'll get a bit of a fatter saddle. I'm still on percocet but I can't deal with the idea that I have to sit around and get fat again. I'm now on a vegan diet so perhaps getting fat fast is less an issue than having all my fitness atrophy. I have bad knees so I'm doubt I can run (my complaints can go on ... ) . If you have any tips for me in terms of just retaining as much cardio fitness as I can it would be greatly appreciated. I'll be back to the bike near the end of our very short summer. I don't expect to gain on my fitness...I just need to limit the damage as much as I can. thanks.